1. Field of the Invention
The present invention relates to a thin film transistor (TFT) substrate and, more particularly, to a TFT substrate which can increase storage capacities of pixels and contact areas of insulating layers.
2. Description of Related Art
In recent years, all the display devices are developed toward having small volume, thin thickness and light weight as the display techniques progresses. Hence, a conventional cathode ray tube (CRT) display is gradually replaced by flat panel display devices such as a liquid crystal display (LCD) device and an organic light emitting diode (OLED) display device. The flat panel display devices can be applied to various fields. For example, the daily used devices such as cell phones, notebooks, video cameras, cameras, music players, navigation devices, and televisions are equipped with the flat panel display devices.
Although the LCD device and the OLED display device are commercially available and especially the techniques for the LCD device are much mature, every manufacturer is desired to develop display devices with improved display quality to meet customers' requirement as the display devices developed. In particular, the structure of the TFT substrate is one factor related to the display quality.
Even though the LCD device and the OLED display device are well developed and commercialized, it is still necessary to develop a display device with improved display quality to meet the customers' requirement.